In a coordinated timing network, multiple distinct computing systems maintain time synchronization to form the Coordinated Timing Network (CTN). Systems in the Coordinated Timing Network employ a message based protocol, referred to as a Server Time Protocol (STP), to pass timekeeping information between the systems over existing high-speed data links. This enables the time of day (TOD) clocks at each system to be synchronized to the accuracy required in today's high-end computing systems. A computing system that provides an STP facility is referred to as a time server or server herein.
A server defined in a Coordinated Timing Network as a primary time server provides primary reference time for the Coordinated Timing Network. The server in a Coordinated Timing Network that determines Coordinated Server Time (CST) (an estimate of the time of day clock for the CTN) based on information from another server in the Coordinated Timing Network is referred to as a secondary time server. The primary time server may obtain its time from an external time source, such as time code receivers, which provide the means to synchronize the time of day clocks in a Coordinated Timing Network to a defined time standard.
Each time server may have one or more time code receivers associated therewith. Currently, when the time code receivers of a primary time server fail, the responsibility of current time server becomes that of a secondary time server, instead of the primary time server. While this may be acceptable in some circumstances; in others, it is not preferred because of the resulting configuration change.